The present invention generally relates to semiconductor packaging and more specifically to an apparatus and method of manufacture of a package for a three terminal device.
One type of semiconductor die package is for a horizontal MOSFET. The package that has source, drain, and gate contacts on one side of the die. In a typical way of forming a semiconductor die for a horizontal MOSFET, drain regions are formed on the same side as the gate and source regions. Because the drain, gate, and source regions are found on the same side of a semiconductor die, contacts for the regions may be formed on one side of the die. In turn, the semiconductor die can be directly mounted onto a circuit substrate with all three contacts contacting the circuit substrate. While producing the semiconductor package for the above semiconductor die is relatively straight forward, the die includes many disadvantages. For example, growing the drain, gate, and source connections on the same side reduces the effective area of the source and also limits the area in which drain contacts may be found. This results in a high “on resistance” (RDSon) per footprint area and also poor thermal performance due to limited drain contacts.
Semiconductor devices have been developed that may include a source region and a gate region on a first side of a semiconductor die and a drain region on a second side that is opposite from the source and gate region. These devices are “vertical” since current passes vertically through the semiconductor die. If the source/gate and drain region contacts are formed on opposite sides of a semiconductor die, the semiconductor die cannot be directly mounted onto a circuit substrate with all three contacts contacting the circuit substrate.
Thus, there is a need for a semiconductor package to address these and other problems individually and collectively.